Conventionally, a method for forming a modified region, which becomes a starting point of cutting, along a line to cut within an object to be processed by irradiating the object with laser light while locating a light-converging point within the object has been known as a method for carrying out a cutting process on the object to be processed such as a semiconductor wafer (for example, refer to Patent Documents 1 to 4). In the processing method, a cutting starting point region is formed by a modified region along a line to cut by irradiating an object to be processed with laser light while scanning a light-converging point with respect to the object. Then, a cutting process of the object is executed with the cutting starting point region used as a starting point.    Patent Document 1: Japanese Patent No. 3408805    Patent Document 2: Japanese Patent No. 3708102    Patent Document 3: Japanese Patent Application Laid-Open No. 2007-75886    Patent Document 4: Japanese Patent Application Laid-Open No. 2006-43713